RedStallion

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I can't believe Tesla's argument is that you have to run their cars below 0 miles of range for it to be a "true test." That is just stupid and another ploy by them to try gaming the "system."
True, no trip planning takes into account running below 0. It's really an emergency and probably killing the battery.
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RedStallion

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1. I was surprised the buffer wasn't bigger on the Mach-E.
2. Every Tesla owner watching this is going to drive their cars an extra 20 miles, or expect them to.
3. It's a good day to be in the towing/mobile charger biz.
4. This still doesn't help get my late MME home.
The buffer is not until the battery is totally exhausted, it would be really detrimental to its life span. It's not like a gallon of gas in the tank after zero reading.
So every manufacturer has to decide where to draw the line. The answer can as simple as Ford decided to preserve the battery even if it means calling a roadside assistance.
 

DaMeatMan

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It's super difficult to estimate SOC. The voltage is flat until it heads steeply downward. This is why the estimate varies after the BEV has sat for a while. (Not the vampire drain).
Any decently designed BMS will be measuring electrons in and electrons out of the pack to determine the state of charge, in other words will have some sort of coulumb meter. Measuring voltage is next to worthless (particularly under load as it sags significantly under load). Voltage of course will be used as part of the equation, particularly for cell balancing, but would not be the main metric used.
 

Woeo

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taycan (+34.1%) wow and mini cooper +36%.
looks like the Tesla Performance models take a pretty bug hit. Hope the GT doesn't follow that trend too closely.
Why would you think GT would follow Tesla trend?
 

DBC

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They may be demanding, but they don't tend to match real world very well in many cases. And real world range is what most people are interested in, and need to know.
When people say they want to see "real world" range what they're actually asking for is their real world range. Unfortunately so many variables affect range -- primarily terrain, temperature, and technique -- that it's impossible for anyone to provide that number. So while people may "need to know" this number, the fact of the matter is that this number isn't knowable. That's just a fact you have to deal with.

In this case the EPA Highway number (IIRC for the MME this is about 245 miles) is lower than the steady 65 MPH test. It's also likely to be lower than the 70 MPH test. That's because the EPA Highway number is essentially an aggressive freeway commuting cycle, which is going to use more energy per mile than driving at a constant speed.

Other than Teslas at one end the the Taycan at the other, the EPA numbers are pretty accurate.
 

DBC

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Any decently designed BMS will be measuring electrons in and electrons out of the pack to determine the state of charge, in other words will have some sort of coulumb meter.
That would be great if you knew the number of electrons in the pack. How would you know that? In fact even new packs don't hold exactly the same number of electrons.
 

dbsb3233

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That's because the EPA Highway number is essentially an aggressive freeway commuting cycle
Just the opposite. It's measured at an average of 48 MPH, with some mathematical adjustments made to estimate highway speed. That's the whole point, it's NOT a real world measure of high speed.
 

dbsb3233

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When people say they want to see "real world" range what they're actually asking for is their real world range. Unfortunately so many variables affect range -- primarily terrain, temperature, and technique -- that it's impossible for anyone to provide that number. So while people may "need to know" this number, the fact of the matter is that this number isn't knowable. That's just a fact you have to deal with.
No, it means you choose a baseline to test that's close to what people are interested in rather than nowhere close (like EPA now is). Like the REAL 65 MPH test here, or the Car & Driver 70 MPH test. Those are real world tests, not back of the napkin math adjustments from a 48 MPH average dynamometer lab test.

Everyone knows you have to adjust for temperature from that. And for cabin climate control use, etc. Those case-by-case things are a given. Sure, it would be a nice extra if they provided upper and lower ranges for those impact too, but first things first. Give us a REAL constant 70 MPH range test in good environmental conditions. The 48 MPH-based projected highway range EPA now gives is wildly off for many models, and thus a poor guide for comparing them.
 

trutolife27

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No, it means you choose a baseline to test that's close to what people are interested in rather than nowhere close (like EPA now is). Like the REAL 65 MPH test here, or the Car & Driver 70 MPH test. Those are real world tests, not back of the napkin math adjustments from a 48 MPH average dynamometer lab test.

Everyone knows you have to adjust for temperature from that. And for cabin climate control use, etc. Those case-by-case things are a given. Sure, it would be a nice extra if they provided upper and lower ranges for those impact too, but first things first. Give us a REAL constant 70 MPH range test in good environmental conditions. The 48 MPH-based projected highway range EPA now gives is wildly off for many models, and thus a poor guide for comparing them.
Yes SIR.
 

StrWhtMME

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The EPA Highway test is far more demanding than either of the tests you're referencing, which is why it reflects a much shorter range than either of these tests will project.
EPA testing is much different than real world driving. I had the test procedures, but unable to locate. Basically done in a lab on a dino, no A/C, temp 70 degrees, and avg speed for city test 21 mph, avg speed for hwy test 42mph. The testing cycle includes varying speeds and stops. That is where an EV has an advantage, benefiting with regen to the battery. I will try to locate the actual EPA drive cycles (city and hwy).
 

DaMeatMan

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That would be great if you knew the number of electrons in the pack. How would you know that? In fact even new packs don't hold exactly the same number of electrons.
Basically what I mean by that is that you are measuring the current flow in and out of the lack, and you know an overall nominal Amp hour capacity for the modules and the pack as a whole which allows you to build in some assumptions for empty and full while under loads, where a voltage reading alone would not be sufficient.

Obviously voltage still plays an important role in measuring the top and bottoms of the pack (particularly when not under load).

As a hobby I've built several lithium battery packs using high capacity 18650 cells, the largest of the packs being 2.2Kwh and I can tell you that I've used similar methods to track and measure the current pack state through a coulometer that does in fact take a reference low voltage as well as reference high voltage to determine empty and full states, then from that point it tracks current in, and current out to determine how much energy is entering and leaving the pack which gives you a far more accurate overall pack state than just looking at voltage alone.
 

TheCats

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That would be great if you knew the number of electrons in the pack. How would you know that? In fact even new packs don't hold exactly the same number of electrons.
You need long-term tracking of the battery capacity, as well as coulomb counting.
And perhaps have it integrated with top- and bottom-balancing of the cells.

Coulomb counting is very useful to avoid excessive current limiting when the BMS can't get accurate instantaneous information. I worked on an EV where the cell connections had different lengths, especially a cable that went from the front to rear battery packs. The expensive commercial BMS had coulomb counting, but didn't use it as a compensating factor. So it would signal the motor controller to shut down under load, usually at an inconvenient time such as pulling away from a stop at an intersection.
 

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Tesla did their runs downhill?
Pulled by a towing!!!


Seriously... to each their own, if you like Tesla go for it... if you prefer the MME go for it, if what gets your pants wet is the ID.4, go for it...

The more BEV on the roads, the more competition that will bring between manufacturers and the cars will only get better and (hopefully) cheaper!
 

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Where range matters is road trips. That's usually highway. In the US, that's usually interstate speeds around the 70-75 MPH area.
Range does matter for city dwellers, too, since most car buyers live in cities, and travel less than 40 miles a day (I am one). This is most important for apartment dwellers who have no charging facilities close by, so they travel once a week (same as for gas cars) to a station and "fill up". Then they drive all week with their charge. So we city dwellers will be most satisfied with any of the EVs that Edmunds tested, but most will prefer the cheaper models with local servicing.
 
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